The Collaborative International Dictionary of English v.0.48:

Hawser \Haws"er\ (h[add]z"[~e]r or h[add]s"[~e]r), n. [From F.
   hausser to lift, raise (cf. OF. hausser['e]e towpath, towing,
   F. haussi[`e]re hawser), LL. altiare, fr. L. altus high. See
   Haughty.]
   A large rope made of three strands each containing many
   yarns.
   [1913 Webster]

   Note: Three hawsers twisted together make a cable; but it
         nautical usage the distinction between cable and hawser
         is often one of size rather than of manufacture.
         [1913 Webster]

   Hawser iron, a calking iron.
      [1913 Webster]

WordNet (r) 3.0 (2006):

hawser
    n 1: large heavy rope for nautical use